Dear Tapan, Remembering efax and stty correctly responding on your computer after some kernel oops, I think you downloaded, built and installed another driver for your modem board which does almost perfectly deal with it. The almost but not totally is the unexpected interaction with the 8250_pci driver (aka serial). Providing you can get hands on its source files, I may port the changes I made to the 537EP driver to unregister the serial driver to avoid the interaction. Yours sincerely, - http://vouters.dyndns.org:8080/ Philippe Vouters (Fontainebleau/France)